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// Noethrion · Brand Book

Brand Book
v0.3

Primary identity, logo system, usage rules — current working draft.

v0.3 · 2026-05-06 · Working Draft

Validation Status

This brand book reflects current working choices. None of the items below are locked yet — they are the best current guess after internal review and will be re-tested before public launch.

// Pending Validation

  • D2 primary mark — visual recognition test (N ≥ 5 reviewers)
  • Color palette — accessibility & brand recall test
  • Baseline rule — readability check at small sizes (16px, 32px)

After validation — either lock or revise. Until then, treat all choices as best current guess, not law.

Mission & Doctrine

The visual identity exists to serve the protocol. Every design choice in this book traces back to a strategic pillar.

Working Primary Mark — D2

D2 is the working primary mark as of 2026-05-06. It is used for consistency across all surfaces during the pre-launch phase. Subject to revision before public launch.

η

Where D2 is currently in use

If in doubt about which logo to use → use D2.

file: assets/logos/D/D2_primary_1024.svg
canvas: 1024 × 1024
η font: Instrument Serif, italic, 400, size 720
η fill: #14F195
baseline: x = 307 → 717, y = 755, stroke 4, round caps, #F5F1E8
background: #0A0A0A (noir)

Color Palette · Working Selection

Three colors carry the entire identity. Every Noethrion surface lives inside this palette.

Noir
#0A0A0A
Background — dark mode surfaces, default canvas.
Signal Green (η)
#14F195
η symbol, accents, primary CTA. The brand color.
Cream (Bone)
#F5F1E8
Baseline line, light text on noir, light-mode background.

These three are the current selection. Pending an accessibility audit before lock. Extended palette tokens (noir-2, bone-2, eta-dim, pulse, terra) exist in the addendum but should be used sparingly.

Typography

The η is the design. Typography around it stays quiet.

η
// Symbol · Display
Instrument Serif
Italic, weight 400. Used only for the η character and editorial display moments.
Aa
// Body · UI
Inter Tight
Weights 300, 400, 500, 600. All body copy, navigation, buttons, marketing copy. Default 300.
[η]
// Code · Tech
JetBrains Mono
Code blocks, technical metadata, mono captions, [η] mono lockups.

Don't mix fonts. If a surface looks busy, remove a font, not add one. The η is the design.

Baseline Rule (Formal)

The horizontal baseline below η is a defining brand element. v0.3 formalizes it.

Semantic meaning

The baseline represents:

Geometric rules (from Addendum §3.2.1)

When the baseline is present, it must be:

D2 implementation (1024 × 1024 canvas, η in fallback Times New Roman Italic)

η visual width measured at ~307px on a 1024 canvas (font-size 720). 55% of that = 168px baseline span, centered on the visual ink center of η.

x1, x2: 423 → 591 (span 168px = 55% of η visual width)
y: 755 (just below η descender)
stroke: 4px, round linecap
color: #F5F1E8 (Cream / Bone)

Note: Instrument Serif Italic does not include Greek glyphs — η renders via the fallback chain (Times New Roman Italic on macOS/iOS, Georgia Italic on some Android). Measurements above are taken from Times New Roman Italic. Visual width in Georgia Italic is ~14% wider; this falls inside the 50–65% addendum range and does not require canvas-specific adjustment.

Visual demonstrations

✓ Correct
η
Centered, below descender, correct width & stroke. This is D2.
✗ Wrong · crosses
η
Line crosses through the η. The baseline must sit below the descender, never through the symbol.
✗ Wrong · off-center
η
Correct width (55%) but shifted left. Baseline must be centered on the visual ink center of η.
✗ Wrong · touches
η
Line touches the η descender. Maintain visible clearance — y=755 minimum on a 1024 canvas with font-size 720.

Logo System — Four Categories

The logo system has four formal categories. Each has a defined purpose and is mapped to specific surfaces in the Usage Matrix.

Category D — Brand Marks (square monograms)

The η on noir. The default brand identity. Used for avatars and primary surfaces.

η
D2
Green η + Bone Baseline
Working Primary
η
D1
Pure Green η
η
D3
Full Green
η
D4
η + Pulse Dot (Signal)

Category E — Mono Marks (technical contexts)

[η] in JetBrains Mono. Required for GitHub, npm, technical docs, terminal screenshots.

[ η ]
E1
Mono Bracket [η]
[ η ] noethrion
E2
Code Label
$ noethrion --status η live
E3
Terminal Style

Category F — Display (editorial / hero)

Editorial compositions for landing pages, pitch decks, banners. Default for marketing surfaces.

// PRIMARY MARK · v0.3 // η = E_useful / E_total η // noethrion · open standard for verifiable energy
F1
Hero Display
// EFFICIENCY · ATTESTATION · ENERGY η NOETHRION Open standard for verifiable energy 1 NOET = 1 kWh · verified
F2
Editorial Vertical
η // PRESENTING Noethrion Open standard for verifiable energy. 1 unit · 1 kWh · cryptographically signed. noethrion.com
F3
Wide Banner

Category G — Contextual (specialized formats)

Avatars, favicons, light mode, official seal. Use when context requires a specific format.

η
G1
Social Avatar
η
G2
Favicon (64×64)
η NOETHRION [email protected]
G3
Email Signature
η
G4
Light Mode
η NOETHRION FOUNDATION EST · 2026
G5
Foundation Seal

v2 archive — historical, do not use for new applications

The v2 series (A1–A4 baselines, B1–B4 line variants, C1–C4 lockups) was the working set before v3 categorization. Archived for historical reference only — not redistributed in this repository. Don't use for new surfaces. Use the v3 D / E / F / G categories instead.

Logo DON'Ts

These are formally prohibited. Violations break brand integrity and must be rejected at design review.

Don't rotate the η. It is upright italic, never angled differently.
Don't change colors. The current palette is locked for consistency, even if not yet validated.
Don't add effects. No drop shadows, glows, embosses, bevels, gradients, or 3D treatments.
Don't crop the η. The full character must remain visible.
Don't break the baseline rule (geometry per Section 7).
Don't stretch. Aspect ratio is always preserved — no horizontal-only or vertical-only scaling.
Don't place on busy backgrounds. Minimum 0.5× η-height clearspace on all sides.
Don't combine η with other letters in a "wordmark style" (only the approved E2 mono lockup).
Don't use η as a bullet point or decorative element in body text. It is a logo, not a glyph.
Don't put η inside circles or shapes (except the approved G5 Foundation Seal).
Don't change the wordmark font. "NOETHRION" is set in Inter Tight Light (300) with letter-spacing.
Don't use the "Initial Development Co." name in branded materials. Always say "Noethrion".
Don't modify provided SVGs without explicit permission from brand stewardship.
Don't create new variants outside the brand stewardship process.

Usage Matrix · Where to Use What

When in doubt about which logo variant fits a context, consult this table. For surfaces not listed, use D2.

Surface Logo Format Notes
Twitter / X avatarD2 / G1Square SVG, 400×400Dark mode optimized
Twitter / X headerF31500×500Wide banner
YouTube avatarD2Square SVGDark
YouTube channel artF32560×1440Use F3 wide composition
GitHub org iconD2 / E1460×460D2 for brand, E1 for dev-first signal
GitHub repo OG imageF31200×630Standard OG dimensions
Discord server iconD2 / G1512×512Dark
Telegram channel logoD2 / G1512×512Dark
Paragraph publicationD2 / F2variesD2 for header, F2 for editorial
LinkedIn company logoG1 / D2300×300Square, dark
LinkedIn cover imageF31584×396Wide banner
Email signatureG3320×80Inline horizontal
Document cover (whitepaper, deck)F1 / F216:9 or A4F1 hero or F2 editorial vertical
Document interior pagesD2 small~80×80 cornerSubtle header watermark
Conference badgeF3 / E2horizontalWordmark visible
FaviconG216/32/64 ICOMulti-resolution; baseline thin
App icon (iOS / Android)D2 / G11024×1024 baseSquare master
Business cardsG4Light mode printInverted noir baseline on bone
Letterhead (formal)G5Top-centerFoundation seal
Legal documentsG5Bottom-centerFoundation seal mandatory
Press releaseF2 / F1Top of releaseEditorial composition
Stickers / merchD1Vinyl-cutPure η, no baseline (small format)
Hardware product labelE1Industrial laser-etchMono bracket holds up to physical wear
Terminal / CLI outputE3ASCII-friendlyUse the prompt-style composition

Validation Testing Protocol

Before locking the primary mark choice, run a structured visual test with at least 5 reviewers. The goal: confirm D2 actually communicates what we think it does, before it's locked into surfaces that are hard to revise later.

Step 1 — solo recognition. Show D2 alone, no context, and ask: "What does this make you think of?" Capture verbatim responses. Don't lead.

Step 2 — comparative match. Show D2 alongside 2–3 alternatives (D1, D3, D4). Ask: "Which feels more like X?" — where X cycles through: seriousness, technology, energy, infrastructure.

Step 3 — record & aggregate. Note feedback patterns. Look for clustering vs. disagreement.

Step 4 — decide.

  1. If N ≥ 5 results land consistently positive → lock D2.
  2. If split or negative → pivot to the next candidate (D1, D3, D4) and re-test.
  3. If no candidate clears the bar → iterate the design, do not force a locked choice.

Until validation completes, treat the working primary as a default — not a commitment.

File Map

All public SVG assets live in assets/logos/{D,E,F,G}/ (repository-relative paths). E / F / G categories are mirrored as the repo grows; D category is fully populated.

IDPathCanvasPrimary use case
D1assets/logos/D/D1_green_eta_pure.svg400×400Tight spaces, stickers, no-baseline contexts
D2assets/logos/D/D2_green_eta_bone_line.svg400×400Working primary — default brand mark
D2-1kassets/logos/D/D2_primary_1024.svg1024×1024High-res master for social avatars
D2-400assets/logos/D/D2_primary_400.svg400×400Standard avatar export
D2-circleassets/logos/D/D2_primary_CIRCLE_1024.svg1024×1024Pre-cropped for platforms that mask avatars (Twitter, Discord)
D3assets/logos/D/D3_full_green.svg400×400Bold statement, high-impact moments
D3-1kassets/logos/D/D3_full_green_1024.svg1024×1024D3 high-res master
D4assets/logos/D/D4_green_eta_pulse_dot.svg400×400"Live" / signal version with pulse dot
E1assets/logos/E/E1_mono_bracket.svg400×400GitHub, npm, technical contexts
E2assets/logos/E/E2_code_label.svg800×200README headers, terminal screenshots
E3assets/logos/E/E3_terminal_style.svg800×200Terminal demos, CLI marketing
F1assets/logos/F/F1_hero_display.svg1200×600Hero sections, presentations
F2assets/logos/F/F2_editorial_vertical.svg600×800Whitepaper covers, vertical posters
F3assets/logos/F/F3_wide_banner.svg1500×500Twitter header, GitHub OG image
G1assets/logos/G/G1_social_avatar.svg400×400Social profile avatars (small-size optimized)
G2assets/logos/G/G2_favicon_64.svg64×64Favicon, app icon base
G3assets/logos/G/G3_email_signature.svg320×80Email footer signature
G4assets/logos/G/G4_light_mode.svg400×400Print, light backgrounds
G5assets/logos/G/G5_foundation_seal.svg500×500Legal documents, certificates